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排序方式: 共有261条查询结果,搜索用时 15 毫秒
1.
2.
Ten captive-reared African black-footed penguins (Spheniscus demersus) from a large outdoor colony were monitored for avian malaria, using several diagnostic tests. One treatment regimen was evaluated. Thin smear blood evaluation enabled detection of seven parasitemias involving Plasmodium relictum and Plasmodium elongatum in the penguins. Leukocytosis (relative lymphocytosis) was characteristic of infected birds. Parasitemia was detected as early as 21 days prior to onset of clinical signs (depression, anorexia, regurgitation, pale mucous membranes, and respiratory distress). The single bird that died had clinical signs only a few hours prior to its death. Treatment consisted of 0.03 mg of primaquine phosphate base/kg body weight, administered orally once daily for 3 days. Oral chloroquine phosphate therapy, given simultaneously, was administered in an initial loading dose of 10 mg of chloroquine phosphate base/kg body weight, followed by doses of 5 mg/kg at 6, 18 and 24 hours after the initial chloroquine dose. This treatment regimen prevented mortality and cleared parasites from the blood. Recurrences of malaria occurred in two birds that had received this treatment. 相似文献
3.
Evidence exists that butyrate inhibits apoptosis of colon crypt cells in vivo so that less tryptophan from cell debris is available for skatole formation by microbes in the pig colon. In this study, potato starch containing a high proportion of resistant starch was fed to test the hypothesis that increased butyrate formation will occur in the colon and contribute to reduced epithelial cell apoptosis, thus leading to reduced skatole formation and absorption. Two groups of six barrows were provided with catheters in the jugular vein and fed either a ration with pregelatinized starch (high ileal digestibility; controls) or potato starch (low ileal digestibility; PS) as the main carbohydrate. All pigs were fed 31 MJ of metabolizable energy and 381 g of crude protein per day. The controls were fed for 19 d. The PS group received the same control ration for 10 d, and then changed to the PS ration. The total feeding period of PS consisted of a 5 d adaptation period followed by another 19 d. In the continously sampled feces, pH, short chain fatty acids, and skatole were determined. Skatole was additionally measured in blood plasma that was sampled daily. After killing barrows at the end of the feeding period, fat tissue for skatole measurement and colon tissue for histological quantification of mitosis and apoptosis were obtained. Feeding potato starch led to a rapid 2.2 fold increase of fecal butyrate when compared both with the control period of the PS group and the control group (P < 0.001). PS feeding resulted in a decrease in pH from 7.3 to 5.3 (P < 0.001) and apoptosis from 2.06 cells/crypt to 0.90 cells (P < 0.01), whereas there was no change in mitosis. Consequently, skatole decreased both in feces (controls vs PS group: 120.0 vs 1.9 microg/g; P < 0.001) and in blood plasma (1.6 vs 0.2 ng/mL; P < 0.001). The mean concentration of skatole in fat tissue was 167 ng/g tissue in controls, and below the detection limit (0.8 ng/g) in the PS group (P < 0.001). It is concluded that butyrate-dependent inhibition of apoptosis in the colon due to potato starch feeding efficiently inhibits skatole production in barrows. Because of the depressed skatole levels, improved sensory quality of pork is possible. 相似文献
4.
Zaghawa A Beier D Abd El-Rahim IH Karim I El-ballal S Conraths FJ Marquardt O 《Journal of veterinary medicine. B, Infectious diseases and veterinary public health》2002,49(3):123-129
In 1989, 220 Holstein Friesian cattle (212 heifers and eight bulls) were imported from Minnesota, USA, to form a closed dairy herd in Arab El-Aoumar, Assiut, Upper Egypt. In November 1996, some abnormal signs such as loss of weight, decreased milk yield, external lymphadenopathy and decreased appetite were observed on this farm. Serological screening by enzyme-linked immunosorbent assay revealed a seroprevalence of antibodies directed against bovine leukaemia virus (BLV) of 37.7% in cattle under 2 years old and of 72.8% in animals more than 2 years old. Diagnosis was confirmed by the detection of BLV proviral DNA using polymerase chain reaction with primers amplifying a fragment of the env gene. Out of 21 tested leucocyte fractions from individual animals, 15 were positive showing a BLV-specific amplicon of 444 base pairs. Analysis of the amplicons for restriction fragment length polymorphisms and DNA sequencing results allowed the isolates to be typed. Since this was the first recorded case of enzootic bovine leukosis in Upper Egypt, strict quarantine measures were adopted and all serologically positive animals in the herd were culled. 相似文献
5.
Mentschel J Deininger MH Schluesener HJ Claus R 《Journal of veterinary medicine. A, Physiology, pathology, clinical medicine》2002,49(4):184-188
The allograft inflammatory factor (AIF-1/daintain) is a hormone-like peptide produced by activated monocytic cells in a variety of traumatic, inflammatory and degenerative lesions. Gut-derived AIF-1 has been shown to modulate insulin production and to attenuate autoimmune diabetes. As the localization of this gastrointestinal peptide in the porcine duodenum is not known and the pig is a convenient model for the study of nutritional modulation of the mucosal immune compartment, we have localized expression of AIF-1 by immunohistology in the duodenum of either malnourished (energy and protein supply 50% of demands, n = 5) or optimally fed pigs (n = 5). AIF-1 macrophages were predominantly located at the villus tip. The number of positively stained cells per high-power field was significantly (P < or = 0.001) higher in the malnourished pigs (74.6 +/- 2.44; least square means +/- SEM) compared to optimally fed pigs (32.56 +/- 1.99). It is likely that the effect in malnourished pigs can be explained by a more pronounced antigen contact of macrophages due to loss of epithelial integrity. Thus, AIF-1 is a novel marker for the study of the nutritional regulation of the mucosal immune system of the pig. AIF-1 expression in the duodenum was further validated by polymerase chain reaction and sequencing. Surprisingly, we detected a slight deviation from the original sequence (probably representing an allelic variation) and an AIF-1 splice variant, previously not known to occur in pigs. 相似文献
6.
An adult Bengal tiger (Panthera tigris tigris) housed in an outdoor sanctuary in Florida exhibited vomiting, diarrhea, and weight loss. A clinical workup did not reveal the source of the clinical signs and antibiotic therapy was unrewarding. Radiographs revealed the presence of an abdominal mass. The tiger died during an immobilization for a follow-up clinical examination. A necropsy was performed and tissue samples of intestine and mesenteric lymph nodes were submitted for histopathologic diagnosis. A pyogranulomatous panenteritis and lymphadenitis with intralesional hyphae led to a presumptive etiologic diagnosis of intestinal/abdominal pythiosis. The diagnosis of pythiosis was confirmed by serology and immunoblotting. 相似文献
7.
Ohne Zusammenfassung 相似文献
8.
Über MaBnahmen zur Bestandssteigerung von Fledermäusennahmen zur Bestandssteigerung von Fledermäusen
Claus König 《Journal of pest science》1961,34(9):138-140
Ohne Zusammenfassung 相似文献
9.
Model studies on reactions occurring in oxidations of lignin with molecular oxygen in Alkaline Media
Basic reactions governing the degradation of lignin in oxidation with molecular oxygen are discussed emphasizing the radical (homolytic) or one-electron transfer-oxidations in the initial phase. The critical oxidation potentials (COP) according to Fieser were found to represent a useful measure for the ease of electron release from lignin-related phenolic models. At low alkalinity rough correlations were observed between the measured COPs and the initial oxygenation rates. The results obtained from quantum mechanical calculations of critical oxidation potentials are briefly discussed.The importance of phenoxy radicals and the hypothetical cyclohexadienone hydroperoxides as intermediates is outlined in view of such degradation reactions as oxidative side-chain eliminations, demethoxylations, and splitting of aromatic rings.Research performed at the Institute of Organic Chemistry, University of Vienna. 相似文献
10.
B. Beier Petersen 《Journal of pest science》1959,32(8):113-117
Ohne Zusammenfassung 相似文献